Low on air done right?

[jjhill]

Just to add my quick two cents, I think that some people here are judging too harshly. I did not get the impression of any emergency or incident at all in this dive. Everyone surfaced with air, there were still two pony bottles remaining as well as air in the other two divers tanks. Sure ideally a shared air situation would not have presented itself, but the newbie went through air faster then anticipated. The situation was recognized and dealt with calmly and efficiently.

The area for improvement as others have mentioned would have been to dive a more conservative plan. The fact that your dive planning consisted of the possibility of a shared air situation perhaps should have tipped you off to a more conservative plan. I'm not saying that the dive plan should not include a plan in case of a low on air situation because every dive should have this discussion but more from a in case of emergency situation and not a i"f you run out during the long underwater swim back to shore" type plan.

At any rate it all turned out well. No one was hurt, no one ran out of air, a potential incident was avoided and a lesson was learned. I say good dive.

 

[nereas]

What happened to the good ol' scubaboard YOU'RE GONNA DIE retort? That's what I expected!

You did get a PADI bash in there, at least. All that's missing is a zinger about pony bottles, please.

If you are wearing a pony bottle, and you are diving with a buddy, it is somewhat of an indictment of your buddy regarding being able to provide you with alternate air. A'la, you don't trust him?

A pony is normally a tool for solo diving. And normally you would want a really big pony bottle, like a 30 or a 40 cu ft. A small pony does you little good.

Go ahead and wear the pony, if that makes you feel safe on a buddy dive.

But sticking with your buddy would be more important, unless you both plan to split up underwater and go your separate ways, or else you don't trust each other to stick together? Or both photographers?

 

[nereas]

...Honestly, I really can't see anything the OP did wrong. They knew he was going to go through his gas quickly and planned accordingly. They planned their dive and dove their plan. Sure the new guy got a little wide-eyed when his guage hit 200 psi but it was far from an emergency.

-Charles

You would "normally" [well trained divers would] turn the dive when the first person reaches 1/2 of your SPG starting pressure.

[Some have posted to the effect that 1/2 is not enough. I do not disagree. However I see 1/2 as the absolute minimum, and feasible, since normally you would head back faster than you headed out, with less if any sightseeing underwater on the return trip.]

You would also normally communicate to each other when you each reached your 1/2-way point.

And by the time you were at 500 psi you would all be on your safety stop.

What is not normal is to blunder around the oceans not paying attention to your own and your buddy's/buddies' SPG pressures. And then think it's amusing afterwards. And then go looking for an atta-boy on Scubaboard because someone in your group went dangerously LOA but it was not you.

Bad plan.

Badly trained divers.

Bad instruction.

Bad situation.

Lucky ending.

Try again.

Pay attention next time more closely to each others' SPGs.

Good luck.

 

[Ber Rabbit]

You also need to take into consideration how fast you and they are moving. New divers often have inefficient kicks that help them burn through their air and they tend to try to go fast which makes it worse. I do a lot of pausing with the newer divers to encourage them to slow down and see what's around them. Slower also gives them a chance to work on their buoyancy control instead of using kicking to maintain their position in the water.

I know one diver who will literally swim circles around his buddy when they are going slow, he likes going fast and feeling like he's "getting somewhere". Make sure that isn't you when you're diving with new divers

New divers are fun to dive with but you do have to make some adjustments when first incorporating them into your stable of buddies. It's as much a learning experience for you as it is for them and diving is all about learning.
Ber :lilbunny:

 

[24940]

You would "normally" [well trained divers would] turn the dive when the first person reaches 1/2 of your SPG starting pressure.

So, as an example... Diving an AL80, starting with 3000psi, you would turn the dive at 1500?

Does anyone else see a problem with that plan?

 

[Web Monkey]

So, as an example... Diving an AL80, starting with 3000psi, you would turn the dive at 1500?

Does anyone else see a problem with that plan?

That would depend on what happens @ 1500. If they start the ascent, or move with the current instead of against it, it's probably OK.

Anything else just means it's a plan to have 0 PSI remaining when they reach the exit.

Terry

 

[jjhill]

I'm sorry. I'm new here and don't have as many dives as you but I find this post a little out of line and over the top.

You would "normally" [well trained divers would] turn the dive when the first person reaches 1/2 of your SPG starting pressure.

You would also normally communicate to each other when you each reached your 1/2-way point.

And by the time you were at 500 psi you would all be on your safety stop.

I don't agree with your halves rule. A dive should be turned at 1/3 pressure leaving 1/3 for the swim back or to the surface while leaving 1/3 as a reserve air that should essentially thought of as your buddies air or emergency air. In this situation it was said the dive was turned at 1400 psi. Which is close to the halves rule you are preaching. In my mind not conservative enough for the newbie.

What is not normal [unless you are a PADI diver, I suppose] is to blunder around the oceans not paying attention to your own and your buddy's/buddies' SPG pressures.

What is with the dig on PADI divers? I myself an a NAUI diver so am not defending PADI from a personal stance but their success is well documented. A divers success or failure does not depend on the agency certifing them but on their individual effort to learn and the skill of instructors teaching them. This can be good or bad regardless of the certifying agency.

And then think it's amusing afterwards. And then go looking for an atta-boy on Scubaboard because someone in your group went dangerously LOA but it was not you.

No where did I get this impression the OP thought this incident was amusing or that he was looking for an atta-boy as you put it. He was looking for thoughts and suggestions on how he can learn from the experience and better himself as a diver. Such desires to learn from one's mistakes to become a better diver should be commended and not criticized.

Bad plan.

I agree the plan should have been more conservative and could have been better.

Badly trained divers.

No evidence of their training being good nor bad

Bad instruction.

No evidence to suggest that his in any way falls on their instructor for improper training

Bad situation.

I don't see this as a bad situation or a particularly dangerous one given there were still two pony bottles and air in two of the divers tanks. I will concede that the situation was not optimal and should have been avoided with better dive planning. I do however commend the OP for looking for ways to improve on his planning.

Lucky ending.

No luck involved. They dove a plan with the possibility in mind that they may have a low on air situation. (Again which should have triggered a more conservative plan) however they had pony bottles and a plan to share air if needed. They had a turn around pressure that they followed (although that pressure should have been more conservative). This ending was not luck at all.

Try again.

Pay attention next time.

I see you have a lot of experience and therefore should have much to share with the diving community. Your thoughts that this could have been handled better is bang on. I do not however see the point in building yourself up while ripping a fellow diver down when they are looking for opinions on how to become a safer more experienced diver. I'm sure that in your beginning there were a few mistakes made too.

Sorry for the post but I guess I get annoyed when someone who comes looking for ways to improve themselves and becomes better divers get flamed in that attempt.

Mistakes should be pointed out and discussed but there is no need to belittle the diver himself.

Rant over.

 

[Ber Rabbit]

So, as an example... Diving an AL80, starting with 3000psi, you would turn the dive at 1500?

Does anyone else see a problem with that plan?

The OP's turn pressure was 1400psi, close enough to half tank for government work. With 100psi more (Nereas turn point) end result would have been similar...300psi instead of 200psi at the surface. Would Nereas have had a different plan? Of course. Anyone who deals with newer divers has their method for planning the dive. The OP doesn't seem to have a lot of experience diving with new divers. The things that would be apparent to seasoned divers in that situation have probably never presented themselves because he dives with a regular buddy. They did their best to come up with a plan that took the available gear and the experience levels of all divers into account. They could have completely skipped that and just done their usual dive profile. Everyone came back alive but the OP realized there were probably better ways to deal with this, hence the term "successful failure". It takes guts to come on here and post these dives but it's a sign the poster is interested in finding a better way to handle the situation the next time it presents itself. It's ok to voice concern over potentially hazardous situations and point out where things could have gone wrong so others can see what possible consequences are but include solutions the poster and those reading the thread can put into practice.

We all make mistakes; this section is where we hear about the mistakes and learn how to avoid them ourselves.
Ber :lilbunny:

 

[ScubaSteve]

I do not believe this will ever get answered if the OP lives up to his word, but was there a current present? Did the return trip happen against the current? That would help explain the additional air consumption that the new diver experienced. It would also point out a brand new major flaw in the dive plan to have stuck with the original plan when turning at half would be into a current.

If there was no current, then disregard this post.

 

[nereas]

...Sorry for the post but I guess I get annoyed when someone who comes looking for ways to improve themselves and becomes better divers get flamed in that attempt.

Mistakes should be pointed out and discussed but there is no need to belittle the diver himself.

Rant over.

I too get annoyed, particularly when I see novices making huge mistakes that endanger even newer novices.

The errors on this dive began during the planning stages, before going into the water.

Wearing different sized tanks was the first error.

Having a 3-man CF was the second.

Not paying close attention to the 3rd novice was the third.

Not proceeding to the safety stop immediately was the fourth.

Four failures. It's quite lucky that no one drowned on this dive.

Half of all scuba fatalities are by novices.

Nice try at a rhetorical reply, JHill. Not one that was very seasoned or logical however. I am sure you will get better at failure analysis with time, however. Everyone does, if they live long enough.